Investigation on Single-Mode-Multimode-Single-Mode Fiber Structure

The multimode interference (MMI) theory and corresponding re-imaging phenomena occurring in a single - mode-multimode-single-mode (SMS) fiber structure is investigated. And the commercially available beam propagation method (BPM) have been adapted and analyzed to model the light propagation in this structure. A detailed simulation study of this structure in terms of the length of the multimode fiber core, the radius of the multimode fiber core, the wavelength of the input light, and the refractive index of the substance surrounding the MMF core has been carried out. Therefore, the fiber structure can be developed as an advanced sensor and widely employed in a wide variety of monitoring fields.